The first and only human disease to be eradicated was smallpox. Epidemiologist William Foege helped lead the campaign and has written a new book about it called "House on Fire: The Fight to Eradicate Smallpox." The World's Lisa Mullins speaks with Foege.

The first and only human disease to be eradicated was smallpox. Epidemiologist William Foege helped lead the campaign and has written a new book about it called "House on Fire: The Fight to Eradicate Smallpox." The World's Lisa Mullins speaks with Foege.